How often should I run System File Checker (sfc scannow) ?

Hi guys,
How often should System File Checker (sfc scannow) be run?
Im curious how others use SFC. Do you run SFC directly before performing a System Backup with Macrium or any other backup software? also....
Do you run SFC before creating a System Restore Point?
Is it advisable to run SFC on a regular basis?

Im asking these questions because in the past even when my system hasn't been showing any errors or problems at all Ive run sfc just to check out of curiosity and its told me that Windows Resource Protection has found corrupt files that couldn't be fixed. Ive then had to run DISM to repair system files.
On one occasion, earlier this week, even though my PC isn't having any problems at all I ran sfc verifyonly . I got the message that Windows Resource Protection has found corrupt files that couldn't be fixed. I ran DISM which told me that nothing need fixing so I typed findstr /c:"[SR]" %windir%\Logs\CBS\CBS.log >%userprofile%\Desktop\sfcdetails.txt into Command prompt and everything was OK there...no errors reported at all. So I ran sfc /scannow which said Windows Resource Protection has found corrupt files that couldn't be fixed...very confusing! I rebooted and ran sfc /scannow again. This time everything was OK-I got the message windows resource protection didn't find any integrity violations.

sportsfan148 said:

Im curious how others use SFC.

I have never used it since I clean installed version 1903, which has been working fine.
I will not use it unless/until something untoward has happened.

Matthew Wai said:

I have never used it since I clean installed version 1903, which has been working fine.
I will not use it unless/until something untoward has happened.

Hi Matthew. I read somewhere that SFC is known for giving false Positives. Is that maybe a reason for not running the SFC routinely on a regular basis as part of system maintenance?

sportsfan148 said:

SFC is known for giving false Positives.

I just found an example: What else can I do to fix the corrupt files?

sportsfan148 said:

Do you run SFC directly before performing a System Backup with Macrium or any other backup software?

Yes.

To me, I'd rather know before I re-image that the problem was not there.

Takes me all of 5 minutes to check.

That said, System File Checker has become a bit of a 'Chicken Little' over the years. Lot's of sky falling that's not really.

More often it's been stupid stuff like shortcut *.lnk's to system utilities. or Defender hash mismatches. Plus, since July of 2019, I've been consistently seeing phantom SFC issues appear after I clean up from an update, either in Storage Sense or, DISM /online /Cleanup-Image /StartComponentCleanup /ResetBase

So this part of my backup routine that at one time had value is rapidly loosing it. ;o|

And as @Try3 has recently pointed out, even Microsoft now recommends DISM be run first, to eliminate and avoid these SFC issues:

Use the System File Checker tool to repair missing or corrupted system files

Try3 said:

As often as you identify that WIndows has a fault.

If Windows crashes
Or if a fault symptom appears that you suspect is caused by Windows itself and if that fault symptom persists in Safe mode
or if, as the SFC tutorial suggests, "some Windows functions aren't working".
then
runningDISM.exe /Online /Cleanup-image /Restorehealth, whilst online, followed by running SFC /ScanNow is worthwhile
else
there would be no point.

No, no, no.


Denis

PS Use the System File Checker tool to repair missing or corrupted system files KB929833 was updated last year and now advises the use of Dism before running SFC.

Great information Denis. I wasn't aware that DISM has to be run before you run SFC now.
I wonder if that is a necessity or just a recommendation to rule out the possibility of SFC showing the Windows Resource Protection has found corrupt files that couldn't be fixed message that SFC sometimes gives and then having to run DISM restorehealth anyway?

- - - Updated - - -

Farvatten said:

Yes.

To me, I'd rather know before I re-image that the problem was not there.

Takes me all of 5 minutes to check.

That said, System File Checker has become a bit of a 'Chicken Little' over the years. Lot's of sky falling that's not really.

More often it's been stupid stuff like shortcut *.lnk's to system utilities. or Defender hash mismatches. Plus, since July of 2019, I've been consistently seeing phantom SFC issues appear after I clean up from an update, either in Storage Sense or, DISM /online /Cleanup-Image /StartComponentCleanup /ResetBase

So this part of my backup routine that at one time had value is rapidly loosing it. ;o|

And as @Try3 has recently pointed out, even Microsoft now recommends DISM be run first, to eliminate and avoid these SFC issues:

Use the System File Checker tool to repair missing or corrupted system files

Hi mate, Thanks for the feedback. That was my reason for asking if it was better to run SFC first routinely before creating a system restore point or system backup so that if there was any SFC corruption it could be fixed first.
From what you say though about SFC now picking up minor things and also false positives Im wondering whether it might be better to only run SFC when your'e having Windows problems

Try3 said:

The KB in the link just says do it but we all know that SFC will normally run without Dism having been done first.
- So I'm going to treat it as just a suggestion and I imagine many others will do the same.

Denis

Thanks for that Denis. I was thinking exactly the same as you